The Nanophotonics research group at Georgia Tech is
led by Prof. Chris Summers in the School of Materials Science &
Engineering.

The groups research goals center on developing and
characterizing new 2D and 3D photonic crystal (PC) materials and
phosphors. Active areas of research include modeling and simulation
of 2D and 3D photonic crystal structures using both the Plane Wave
Expansion (PWE) and Finite-Difference Time-Domain (FDTD) methods.
Experimentally, we have several members focused on fabricating inverse
opal structures. Our primary method of opal infiltration is Atomic
Layer Deposition (ALD), and we have built ALD reactors for oxide
(TiO2, Al2O3, ...) and phosphide
(GaP, InP, ...) thin film growth. We also have several students
working on luminescent quantum dots and phosphors for incorporation
into photonic crystal structures. More information about our research
areas can be found by following the links below.

2D Photonic Crystals:

Our effort is directed to the design and fabrication of novel
two-dimensional photonic crystals for controlling light. Currently we
are pursuing new concepts to obtain very large and tunable refraction
and dispersion properties, and to reduce beam divergence and to focus
propagating beams.

3D Photonic Crystals:

Our primary thrust is to investigate and to develop novel wide
photonic band gap three-dimensional PC architectures for generating
and controlling light. A major focus of our effort is designing and
fabricating inverse opal-based structures using atomic layer
deposition and selective etching. Luminescent properties have been
obtained by incorporating phosphor or QD materials into the structures
and dynamical tuning by the infiltration of nematic liquid
crystals. Recently, holographically defined polymer templates have
been infiltrated and inverted by these techniques.

Conventional & Quantum Dot Phosphors:

New luminescent materials are being developed for displays, solid state
lighting and X-ray imaging applications. Currently, non Cd-based technologies
for solid state lighting are being developed based on III-V quantum dot (QD)
materials that enable the whole visible spectral range to be covered. Also,
coating techniques are being developed to control both QD size and surface
recombination properties. Future work will be directed to the formation of
core/shell structures and the synthesis of doped nano-particles. The
investigation of X-ray phosphors is directed to the development of high
efficiency ZnTe:O doped materials prepared by a dry synthesis method.

Nanotechnology & Spintronics:

In cooperation with Professor Wang's and Professor Ferguson's programs, the
properties of ZnO nanowires, nanorods and nanobelts are being investigated and
work is being performed on the development of spintronic materials and
devices.

Atomic Layer Deposition:

New protocols for atomic layer deposition have been developed,
primarily in support of the 3D photonic crystal program, which
involves the infiltration of highly porous opal and holographically
formed templates. Materials investigated include, TiO2,
Al2O3, ZnO, ZnS:Mn and GaP and InP. Recent
efforts include hermetically coating phosphors and related display
material structures.